论文标题
密度矩阵重新归一化小组在两个维度中的列表研究：在平方晶格上应用于旋转$ 1 $ biinear-biquadratic模型
Density Matrix Renormalization Group Study of Nematicity in Two Dimensions: Application to a Spin-$1$ Bilinear-Biquadratic Model on the Square Lattice
论文作者
论文摘要
列秩序是在几个强相关系统（例如铁基超导体）中观察到的异国特性。使用大尺度密度基质重新归一化组（DMRG）技术，我们在零温度上研究与自旋偶极和四极阶竞争的列型自旋液体。我们使用这些列表来表征不同的量子相和量子相变。更具体地说，我们研究了一个旋转$ 1 $ $ 1 $双线性 - 二重的海森堡模型，并在最近的邻居以外的耦合方面进行了旋转。我们专注于高度对称$ su（3）$点的参数区域，其中双线性相互作用和生物段相互作用相等。随着进一步的邻次二次相互作用，我们确定了不同的自旋偶极和四极阶。我们发现，DMRG会导致圆柱几何形状正确检测到不同量子状态的nematicity，并准确地表征了它们之间的量子相变。因此，自旋驱动的nematicition-在此定义为在90 $^o旋转下晶格不变性的自发断裂 - 是一个订单参数，可以直接在不同量子状态下的二维计算中直接研究DMRG计算。
Nematic order is an exotic property observed in several strongly correlated systems, such as the iron-based superconductors. Using large-scale density matrix renormalization group (DMRG) techniques, we study at zero-temperature the nematic spin liquid that competes with spin dipolar and quadrupolar orders. We use these nematic orders to characterize different quantum phases and quantum phase transitions. More specifically, we study a spin-$1$ bilinear-biquadratic Heisenberg model on the square lattice with couplings beyond nearest neighbors. We focus on parameter regions around the highly symmetric $SU(3)$ point where the bilinear and biquadratic interactions are equal. With growing further-neighbor biquadratic interactions, we identify different spin dipolar and quadrupolar orders. We find that the DMRG results on cylindrical geometries correctly detect nematicity in different quantum states and accurately characterize the quantum phase transitions among them. Therefore, spin-driven nematicity -- here defined as the spontaneous breaking of the lattice invariance under a 90$^o$ rotation -- is an order parameter which can be studied directly in DMRG calculations in two dimensions in different quantum states.
